tdf#65038: use trailing string characters for look-ahead assertions

... like commit eb973a46ba0e34026db2d2929f2aa10505623872 did for
look-behind assertions

Change-Id: I86ece5d3ee49b0c5d86f2cfab5fed2830d5ad777
Reviewed-on: https://gerrit.libreoffice.org/85487
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

2 files changed, 24 insertions, 3 deletions

diff --git a/i18npool/source/search/textsearch.cxx b/i18npool/source/search/textsearch.cxx
index b0361bee89a3..c74e158780f4 100644
--- a/i18npool/source/search/textsearch.cxx
+++ b/i18npool/source/search/textsearch.cxx
@@ -323,9 +323,16 @@ SearchResult TextSearch::searchForward( const OUString& searchStr, sal_Int32 sta
             const sal_Int32 nMaxLeadingLen = aSrchPara.searchString.startsWith("(?") ? 100 : 3;
             nInStartPos -= std::min(nMaxLeadingLen, startPos);
         }
+        sal_Int32 nInEndPos = endPos;
+        if (pRegexMatcher && endPos < searchStr.getLength())
+        {
+            // tdf#65038: ditto for look-ahead assertions
+            const sal_Int32 nMaxTrailingLen = aSrchPara.searchString.endsWith(")") ? 100 : 3;
+            nInEndPos += std::min(nMaxTrailingLen, searchStr.getLength() - endPos);
+        }
 
-        css::uno::Sequence<sal_Int32> offset(endPos - nInStartPos);
-        in_str = xTranslit->transliterate( searchStr, nInStartPos, endPos - nInStartPos, offset );
+        css::uno::Sequence<sal_Int32> offset(nInEndPos - nInStartPos);
+        in_str = xTranslit->transliterate(searchStr, nInStartPos, nInEndPos - nInStartPos, offset);
 
         // JP 20.6.2001: also the start and end positions must be corrected!
         sal_Int32 newStartPos =
@@ -907,7 +914,8 @@ SearchResult TextSearch::RESrchFrwrd( const OUString& searchStr,
 
     // use the ICU RegexMatcher to find the matches
     UErrorCode nIcuErr = U_ZERO_ERROR;
-    const IcuUniString aSearchTargetStr( reinterpret_cast<const UChar*>(searchStr.getStr()), endPos);
+    const IcuUniString aSearchTargetStr(reinterpret_cast<const UChar*>(searchStr.getStr()),
+                                        searchStr.getLength());
     pRegexMatcher->reset( aSearchTargetStr);
     // search until there is a valid match
     for(;;)
diff --git a/sw/qa/extras/uiwriter/uiwriter.cxx b/sw/qa/extras/uiwriter/uiwriter.cxx
index cc51519f61fd..4790a602bbbf 100644
--- a/sw/qa/extras/uiwriter/uiwriter.cxx
+++ b/sw/qa/extras/uiwriter/uiwriter.cxx
@@ -2284,6 +2284,19 @@ void SwUiWriterTest::testTextSearch()
     // check of the end result
     CPPUNIT_ASSERT_EQUAL(OUString("xCelqy xWorqd xThzq xis xa xtasq"),
                          pCursor->GetNode().GetTextNode()->GetText());
+    // regex: use positive look-ahead assertion
+    xReplaceDes->setSearchString("Wor(?=qd xThzq xis xa xtasq)");
+    xReplaceDes->setReplaceString("&p"); // testing & reference
+    ReplaceCount = xReplace->replaceAll(xReplaceDes);
+    CPPUNIT_ASSERT_EQUAL(sal_Int32(1), ReplaceCount);
+    // regex: use negative look-ahead assertion
+    xReplaceDes->setSearchString("x(?!Worpqd xThzq xis xa xtasq)");
+    xReplaceDes->setReplaceString("m");
+    ReplaceCount = xReplace->replaceAll(xReplaceDes);
+    CPPUNIT_ASSERT_EQUAL(sal_Int32(5), ReplaceCount); // one of the 6 "x" must not be replaced
+    // check of the end result
+    CPPUNIT_ASSERT_EQUAL(OUString("mCelqy xWorpqd mThzq mis ma mtasq"),
+                         pCursor->GetNode().GetTextNode()->GetText());
 }
 
 void SwUiWriterTest::testTdf69282()